Mortadella Sandwich Recipe

Prep the bread

Slice the rolls horizontally. If you prefer a warm sandwich, lightly toast the cut sides under a broiler for 1–2 minutes until golden; otherwise proceed untoasted.

Mix the softened butter, Dijon mustard, and mayonnaise in a small bowl until smooth. Spread evenly on both cut sides of the bread (butter-mustard-mayo on one side, plain mayo-butter on the other) to create a flavorful barrier that keeps the bread from getting soggy.

Arrange half of the mortadella slices on the bottom half of each roll, folding as needed to build an even layer. Top the mortadella with two slices of provolone or fontina per sandwich, distributing the cheese evenly.

If you want the cheese slightly melted, place the assembled bottom halves under a broiler for 30–60 seconds, watching closely until the cheese softens and just begins to bubble.

Thinly slice the tomato and the red onion into rings. Lightly season the tomato slices with about 1/8 tsp salt and a grind of black pepper. Drain any excess moisture with a paper towel to keep the sandwich from becoming soggy.

Layer lettuce (or arugula) on top of the cheese, then add the seasoned tomato slices, a few rings of red onion, and the sliced pepperoncini. Distribute the vegetables so each bite has a balance of components.

Drizzle about 1/2 tsp olive oil and 1/4 tsp red wine vinegar over the vegetables (split between the two sandwiches). Sprinkle the remaining salt and freshly ground black pepper evenly.

Place the top half of the roll over the fillings. Press down gently, slice the sandwich in half if desired, and serve immediately.